feat: rcl unit test

[YuanYuYuan]

This PR implements comprehensive unit test coverage for the rcl-z ROS 2 client library,
ported from the upstream ROS 2 rcl test suite.

The implementation includes critical bug fixes, feature additions, and improvements to align with ROS 2 behavior.

Closes #20.

Summary:

• 24,000+ lines of test code added across 24 test modules
• Full implementation of RCL arguments parsing system
• Event handling support for QoS events
• Graph API enhancements for topic and node discovery
• Topic name validation utilities
• Multiple bug fixes in core functionality (waitsets, services, timers, publishers, subscriptions)

Changes

New Features

Arguments System (src/arguments.rs)

• Complete implementation of RCL arguments parsing (--ros-args, --param, --remap, etc.)
• Support for parameter files (--params-file)
• Log configuration flags (stdout, rosout, external libs)
• Enclave specification
• Validation for remap rules, parameter rules, node names, and namespaces

Event System (src/event.rs)

• QoS event handling for publishers and subscriptions
• Event types: offered/requested deadline missed, incompatible QoS, liveliness changed, message lost
• Event subscription and triggering support

Topic Name Validation (src/validate_topic_name.rs)

• Topic name validation (characters, structure, substitutions)
• Topic name expansion (with node name/namespace)
• Full/relative topic name resolution

Test Coverage

Core functionality tests:

• test_init.rs - Initialization and shutdown sequences
• test_context.rs - Context lifecycle management
• test_node.rs - Node creation, naming, namespaces
• test_arguments.rs - Argument parsing validation

Communication tests:

• test_publisher.rs - Publisher lifecycle, loaned messages, actual QoS
• test_subscription.rs - Subscription lifecycle, message reception
• test_service.rs - Service lifecycle, request/response handling
• test_client.rs - Client lifecycle and service calls

Time and synchronization tests:

• test_time.rs - Time points, durations, conversions
• test_timer.rs - Timer lifecycle, callbacks, cancellation
• test_wait.rs - Waitset operations and blocking behavior
• test_guard_condition.rs - Guard condition triggering

Graph and discovery tests:

• test_graph.rs - Topic/service graph queries
• test_info_by_topic.rs - Publisher/subscription info by topic
• test_get_node_names.rs - Node discovery and enumeration
• test_count_matched.rs - Publisher/subscription matching counts

QoS and configuration tests:

• test_get_actual_qos.rs - Actual QoS retrieval and verification
• test_events.rs - QoS event handling
• test_domain_id.rs - Domain ID configuration

Utility tests:

• test_namespace.rs - Namespace handling
• test_expand_topic_name.rs - Topic name expansion
• test_validate_topic_name.rs - Topic name validation
• test_msgs_support.rs - Message type support helper crate

Bug Fixes

Initialization Issues

• Fixed null pointer initialization in waitsets (proper ..Default::default() usage)
• Fixed FastCDR deserialization issues
• Proper cargo clippy field_reassign_with_default handling

Service Implementation

• Refactored to non-blocking service calls
• Fixed test logic alignment with ROS 2 behavior
• Proper request/response handling

Publisher/Subscription

• Fixed ROS_DISABLE_LOANED_MESSAGES environment variable handling
• Aligned QoS profiles with ROS 2 defaults
• Local discovery improvements in graph operations

Timer System

• Enhanced timer lifecycle management
• Fixed timer cancellation and reset logic

Infrastructure Improvements

Build System (flake.nix, Cargo.toml)

• Split test environments: testCore (no test_msgs) vs testFull (with test_msgs)
• Feature flags: test-core, test-msgs, test-all
• Added test-msgs package dependencies for comprehensive testing
• CI workflow now runs clippy with --all-targets --all-features

Type Support (build.rs)

• Additional RMW function bindings for matched counts
• Auto-detection of test_msgs availability via has_test_msgs cfg
• Extended bindgen allowlist for testing APIs

Code Organization

• Added license headers (Apache 2.0, Copyright 2025 ZettaScale Technology)

[CLAassistant]

All committers have signed the CLA.